Neighbourhood tool lending rotation calculator

Calculate proposed loan schedule and requests assigned with your own figures.

Your numbers

Use the units shown. Results update as you change valid inputs.

Use proposed loan schedule and requests assigned to compare changes to your inputs. The method and limits below explain the scope.

Examples

Examples

Try the starting example

Tool inventory: tool name, available units
Drill,1
Requests: person, tool, earliest day, loan days, latest start day
A,Drill,1,2,1 B,Drill,2,1,4 C,Drill,2,1,3
Return/reset buffer days
1
Proposed loan schedule (end day exclusive)
A: Drill#1 1–3; B: Drill#1 4–5
Requests assigned
2
Unmet requests
C
Distinct physical tool units used
1

Try another scenario

Tool inventory: tool name, available units
Drill,1
Requests: person, tool, earliest day, loan days, latest start day
A,Drill,1,2,1 B,Drill,2,1,4 C,Drill,2,1,3
Return/reset buffer days
0
Proposed loan schedule (end day exclusive)
A: Drill#1 1–3; C: Drill#1 3–4; B: Drill#1 4–5
Requests assigned
3
Unmet requests
None
Distinct physical tool units used
1
Calculation method

Calculation method

Proposed loan schedule (end day exclusive)

Process requests by latest start, then input order. Choose the tool unit with earliest availability; start=max(earliest day, unit availability) if no later than latest start.

Requests assigned

Count feasible assignments under this order.

Unmet requests

Requests that cannot meet their supplied latest start or lack a matching tool.

Distinct physical tool units used

Count different tool/unit indices receiving at least one assignment. End day is the first day after the loan; the return buffer begins then.

Symbols and units
a
Tool inventory: tool name, available units
b
Requests: person, tool, earliest day, loan days, latest start day
c
Return/reset buffer days

Use the units shown. A list keeps the order in which you enter its values. The symbol ^ means “raised to the power of”.

Assumptions & limits

Assumptions & limits

  • A finite-inventory earliest-deadline loan proposal, with explicit reset buffer and end-exclusive loan dates. It does not approve borrowers, reserve real tools or prove maximum possible request satisfaction.
Are these inputs private?

These calculations run in your browser. A shared link contains the values you choose to share. Only questions submitted to the separate AI finder are sent to OpenAI.

Further reading

OpenStax: arithmetic and geometry ↗

Background reading; this does not imply endorsement or independent review of SumFizz.

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